Sheet feeding apparatus



3 Sh'dets-Sheei L. BAKER SHEET FEEDING APPARATUS June 12, 1951 Filed March 4, 1946 fiaz aflm ATTORNEY June 12,1951 BAKER 7 2,556,895

SHEET FEEDING-APPARATUS 7 Filed March 4, 1946 v 5 SheetsSheet 2 v INVENTOR ATTORNEY June 12, 1951 L. BAKER SHEET FEEDING APPARATUS I5 Sheets-Sheet 3 Filed March 4, 1946 INVENTOH ATTORNEY Patented June 12, 1951 UN TED S ES ATENT OFFECE I 2,556,895 sneer FEEDING APPARATUS tiqa ofew York Application March 4, 1946, Serial No. 651,727

11 Claims. 1

This invention relates to sheet feeders and more particularly to sheet detecting mechanisms thereof employed to detect an abnormal condition in the feed of sheets and transmit the result or effect of the detecting operation to control means.

One of the objects of the present invention is to provide in a sheet feeder novel sheet detecting mechanism for detecting the failure of said feeder to feed a sheet during normal operation thereof and feeding of sheets thereby, or the absence of a sheet at a time when and at a place Where a sheet should normally be present.

7 Another object of the invention is to provide in a sheet feeder novel absence sheet detecting mechanism wherein the result or effect of the absent sheet detecting operation is controlled by a member movable periodically across the sheet path.

Another. object is to provide in a sheet feeder novel absence sheet detecting mechanism associated with sheet calipering or exces's'sheet detecting mechanism in a novel manner, whereby the absent sheet detecting operation and the sheet ,calipering or excess sheet detecting operation may be performed simultaneously and at a time in each cycle of operation of the feeder when a sheet should normally be present for said detecting operations.

A further object is to provide in a sheet feeder adapted to feed a group or plurality of sheets in side by side relation to a machine or instrumentality acting on said sheets in like manner, novel means for preventing presentation to said machine or instrumentality of a group of sheets 3,

which would cause an unbalancedconditionin the machine or instrumentality.

A Still further object is to provide in a sheet feeder of the above character, a novel arrangement of sheet calipering or excess sheet detecting mechanisms for preventing presentation of the group of sheets to the machineor instrumentality in the event any one of said sheets contains an excess sheet or is of a thickness greater than the thickness of a normal single sheet.

Another object is to provide in a plural-sheet feeder of the above character novel absence sheet detecting means for preventing presentation of a group of sheets to a machine or instrumentality in the event one of the sheets of said group is not present at the time of the sheet detecting operation.-

Still another object is to provide in a sheet feeder adapted to feed a group or plurality of associated with sheet calipering or excess sheet detecting mechanisms in a novel manner for rendering sheet reject or throw-out means effective upon failure of said feeder to feed one or more of said sheets, or in the event any one ofthe fed sheets contains an excess sheet or is of a thickness greater than the thickness of a normal single sheet.

The above and further objects and novel features' of the present invention will more fully appear from the following detailed description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only, and are not intended as a definition of the limits of the invention, reference for this latter purpose being had primarily to the appended claims.

In the drawings, wherein like reference chap acters refer to like parts throughout the several views,

Fig. l is a vertical longitudinal sectional view of a sheet feeder employing sheet detecting mechanisms constructed, arranged and operated in accordance with the present invention, said view being taken substantially on the line I of Fig. 2;

Fig. 2 is a top planview of said feeder, with parts omitted for purposes of clearer illustration;

Fig. 3 is an enlarged vertical longitudinal section on the line 33 of Fig. 2;

Fig. 4 is a front elevation, partly in section, of the portion of the feeder shown in Fig. 3;

Fig. 5 is a vertical longitudinal section on the line 5-5 of Fig. 4;

Fig. ,6 is an enlarged detail front elevation, partly in section, of a sheet calipering roller, and mounting and driving means therefor;

Fig. 7 is an enlarged vertical longitudinal section on the line l'! of Fig. 2; and

Fig. 8 is a front elevation, partly in section, of the portion of the feeder shown in Fig. 7.

Referring to the drawings, there is shown a sheet feeder of the general type disclosed in the United States Patent No. 2,247,466, granted July 1, 1941, to Leonard Baker and Leo C. Williams, but adapted to feed a group of metallic sheets from a plurality of piles of said sheets arranged in side by side relation and deliver the fed sheets in like manner to a tinning pot or machine for applying a coating of tin on both surfaces there of. It will be understood that the feeder may aseaeos 3 be employed for feeding a group or plurality of metallic sheets in side by side relation to machines other than tinning machines, such as, for example, lithographing presses, varnishing machines, buffing and cleaning machines, and slitters, and may also be employed for feeding a plurality of cardboard or other relatively stiff sheets in side by side relation to printing presses, cutting and creasing machines, and various other machines which are devised to operate on one or both surfaces of said sheets.

As shown, is and ii indicate portions of the side frames of the feeder on which are mounted the various movable parts as well as certain stationary parts of said feeder. Side frames 50, ll are connected together at the tops thereof by two longitudinally spaced, transversely extending tie bars l2 and i3, and at a point intermediate the upper and lower ends thereof by two similar tie bars i4 and 55. Tie bars i2, i3 and M, 95 are secured at their opposite ends to the upper and lower ends, respectively, of vertically extending side brackets it and i? which, in turn, are secured to the side frames til, M, respectively.

The various movable parts of the feeder are driven from any suitable source of power (not shown) by a chain it (Fig. 2) which passes around a sprocket l3 that is secured to the outwardly projecting end of a short drive shaft 23. The latter extends through a suitable opening in the side frame H) and is journalled in a suitable bearing in the side bracket [6. Fixed on shaft 2i and disposed between side frame It and bracket [6 is a spur pinion 2! (Fig. 4) which meshes with a spur gear 22 that is fixed on and drives a cam shaft 23. The latter extends transversely of the feeder and is journalled in suitable bearings in the side brackets 16, El, and in a plurality of transversely spaced intermediate or center brackets 24 (Figs. 1 to 4) which are secured to the tie bars !2, l3 and extend downwardly therefrom, there being three of said center brackets shown for reasons to appear hereafter. Shaft 23 makes one revolution for each cycle of operation of the feeder and is utilized to operate various parts of said feeder to be hereinafter described.

The feeder includes a pile elevator comprising cross beams 25 (Fig. 1), one only being shown, adapted to support a pile board 26 and a plurality of piles of metal or other sheets arranged in side by side relation on said pile board. As shown in Fig. 2, the feeder is designed to operate on a maximum of three piles of sheets which are indicated at 21, 21a, and 27b, and arranged side by side in slightly spaced relation. The cross beams 25 have their opposite ends engaged over longitudinally extending side bars 23, each one of which is connected at its front and rear ends with flexible cables 29 and 3t, respectively, (Figs. 1 and 2). The cables 29, 30 at opposite sides of the feeder extend upwardly from the side bars 23 and pass around suitably grooved sheaves journalled on the side frames [0, i i adjacent the front and rear thereof, the front sheaves only being shown and indicated at 3!. From the sheaves 35 the cables 29, 30 extend to a suitable elevator operating mechanism (not shown) for raising the elevator step by step in the usual manner in order to maintain the tops of the piles 21, 2'i'a, and 21b at the proper level as the sheets are fed therefrom in succession by means for this purpose hereinafter described. For a more detailed description of the pile elevator, its operating mechanism and control means, reference may be had the above-mentioned United States Patent No.

2,247,466. During step by step upward movement of the elevator, the front sides of the piles of sheets 21, 21a, and 21b bear against and are guided by a metal apron or plate 32 which is secured to the lower tie bar it.

The upper rear opposite corner portions of the piles of sheets 21, 21a, and 27b are first winded by suitably winding devices (not shown) to preliminarily separate the opposite rear corner portions of the uppermost sheets of said piles, whereupon the topmost sheets of the piles ZE, 21a, and 212) are simultaneously engaged at their opposite rear corner portions by suitable suction devices (not shown) and lifted to further separate the same from the next or underlying sheets. The pile winding devices and the suction sheet lifting devices may be of the general type disclosed in the above-mentioned United States Patent No. 2,2a7,466 which may be referred to for a more detailed description as to the construction, mounting, and operation thereof.

After the top sheets of piles 21, 21a, and 210 have been simultaneously lifted at the rear thereof by the suction devices as described, and have been further winded by winding devices (not shown) to completely separate the same from the next sheets therebelow, said top sheets are simultaneously forwarded from said piles by suction sheet forwarding devices located at the front of the feeder. These suction sheet forwarding devices comprise cylinders 33 (Figs. 1 and 2) and suction cups 34 that are moved up and down relative to said cylinders through the making and breaking of vacuum therein to engage each sheet at transversely spaced points and lift said sheet from its respective pile prior to forwarding of the same therefrom. The sheet forwarding devices are constructed and operated in the same manner as the sheet forwarding devices disclosed in the United States Patent No. 2,247,466 above referred to and need no detail description herein.

The sheet forward devices have swinging movement imparted thereto to forward the sheets from the piles 21, 21a, and 211). For this purpose, the cylinders 33 are secured to arms 35 which, in turn, are adjustably fixed on a transversely extending rock shaft 36 that is journalled in suitable bearings in brackets 31 secured to side frames H}, l!. The sheet forwarding devices are rocked forwardly by a cam 38 that is fixed on and rotated by cam shaft 23' and engages a roller 39 journalled on a cam strap 49 extending over said cam shaft and pivotally connected with an arm M which, in turn, is fixed on rock shaft 3E. The sheet forwarding devices are rocked rearwardly by a spring pressed rod 42 (Fig. 2) having one end thereof pivotally connected with an arm 43 fixed on rocl: shaft 36 and the opposite end guided in a suitable opening in the upper tie bar l2. The spring for rod 42 is indicated at M and encircles said rod between tie bar [2 and a collar 45 adjustably secured to said rod.

Vacuum is created and broken in the cylinders 33 and suction cups 34 at predetermined intervals to cause said cups to simultaneously engage, grip, and lift the top sheets from the piles 2'1, 21a, and 211) when the sheet forwarding devices have been swung rearwardly, and to releasesaid sheets when the sheet forwarding devices have completed their forward movement and delivered the sheets engaged thereby in side by side relation onto conveying means to be hereinafter described. For this purpose, the cylinders 33 have connected therewith corresponding ends of flexible conduits 46 the opposite ends of which are connected with by the sheet separating devices are simultaneous-' ly engaged and lifted at the front thereof by the sheet forwarding devices and delivered thereby in spaced side by side relation to conveying means that advance said sheets in like manner to.

the timing pot or other instrumentality with which the feeder is associated. As shown, the conveying means comprise wide and narrow feed rollers 4! and 48, respectively, drop rollers 49 cooperating with the narrow feed rollers 48, and conveyor tapes 50 passing around the wide feed rollers 41 (Figs. 2, 3, and 4). The feed rollers 41,

48 are fixed in spaced relation on a shaft 5| and are alternately arranged on said shaft in a manner, such that each sheet delivered thereon from the piles 2i, Z'ia, and 2112 by the sheet forwardin devices will be properly supported and prevented from sagging by a plurality of said alternately arranged feed rollersand by a plurality of the tapes 5!] during forward movement thereof toward the tinning pot or other instrumentality. Shaft, 5|.extends transversely of the feeder and is journalled in suitable bearings in the side brackets it, I1 and in a plurality of transversely spaced intermediate or center brackets 52 (Figs. 2, 3, 4, and 6) which are secured to the lower tie bars M, thcrebeing three of said center brackets shown corresponding to the number of piles of sheets 21, 21a, and 21b for reasons to appear hereafter. The shaft 5!, feed rollers 41, 38 and conveyor tapes 59 passing around the feed rollers 41 are driven continuously by suitable gearing including a'spur pinion 53.. (Fig. 4) fixed on said shaft and which meshes with a spur gear 54 that is secured to or formed integrally with spur pinion 2! on drive shaftZfl.

The drop rollers 49,are journalled on arms 55 (Figs.v 2 and4) which are fixedin spacedrelae tion on arock shaft 56 and in a manner so that each sheet delivered between said drop rollers and the feed rollers 41, 48 from the separate piles 21, 21a, and 21b by the sheet forwarding devices will be engaged at transversely spaced points by at least two drop rollers, thereby assuring forward movement of the sheets in a straight line and in spaced parallel paths toward the tinning otor other instrumentality, The rock shaft 5E extends transversely of the feeder and is jour-,

nalledin suitable bearings in side plates 5'! and Eilprojecting forwardly of the feeder and secured to the side brackets 16, ll. Additional supports and bearings for rock shaft 55 are provided by brackets 59- (Figs. 1 and 4) which are secured to the center brackets 24 and project downwardly therefrom tq receive said shaft. 7 The drop rollers 45*. are. raised and lowered at predetermined intervals and the operation thereof is so timed that they are raised when the sheet forwarding devices deliver the sheets from the piles 2'1, 21a, and 21b onto the feed rollers 41, 48 and tapes 5!), and. are lowered after such delivery and breaking of vacuum in the sheet forwarding devices to engage said sheets until they have been substantially entirely advanced from said piles by the cooperating feed rollers 48 and the tapes 5i), whereupon said drop rollers are again raised !5 and project upwardly therefrom,

tinning pot or machine.

6.. and forward movement of the, sneeus in side by. side relation toward the tinning pot or other: instrumentality is continued by the tapes 50... The drop rollers 59 are lowered by a spring (not shown) and are raised by a cam 6i) '(Fig, '2) which is secured to cam shaft 23 and engages a roller; 6'! journalled on an arm 62 that is fixed. on rock: shaft 56. If desired, the drop rollers 49 maybe arranged to continuously engage the feed. rollers :lB by disconnecting the arm filfrom shaft. 55, Dr; by moving said arm and therewith roller 61 out. of the path of action of cam 60.

It will appear that with the construction thus. far described, in the normal. operation of the feeder and during successive cycles of operation. thereof, the sheets are forwarded simultaneously from the top of pilesZl, 21a, and 21bby the sheet forwarding devices 33, 34 and delivered thereby in side by side relation to the feed rollers 41, 48,

, drop rollers 49, and conveyor tapes 50 which advance said sheets in like manner to, the tinning pot or other instrumentality for further action: thereon.

In the feeding of sheets and particularly a. group or plurality of sheets in side by Side relation to a tinning pot or other machine which acts"- on one or both surfaces of said sheets, it is desirable that only single Sheets and sheets of a,- uniform thickness should be presented to said If, for example, in the illustrated embodiment, the sheet. fed from either the pile 21 or pile 21b isaccompanied by or con tains an additional sheet adhering thereto, or is of a thickness greater than the normal thickness of the remaining two sheets fedsimultaneously therewith, the excess sheet or. excess thicknesssheet will, on the one hand, cause possible injury to the tinning pot or other machine; and on the other hand will create an unbalanced condi- I tion in the tinning pot or machine with the result that all the sheets will not he roperly coatedv or acted upon and, hence, must be scrapped. If the sheet fed from pile 27a is accompanied by. or contains anadditional sheet adhering there-,. to, or is of a thickness greater than the normal thickness of the sheetsfed simultaneously therewith from the piles 2! and 21b, the excesssheet or excess thickness sheet, while it might not cause an unbalanced condition in the tinning potor other machine, it will cause possible injury to the", tinning pot or machine, and prevent proper coating of or action on all the sheets with the re,- sult that said sheets would also have to be scrapped. v r

In accordance with the present invention, sheet calipering or excess sheet detecting mechanisms are provided which are arranged in a novel manner and associated with the conveying means to caliper the sheets during forward movement thereof in side by side relation and prevent presentation of all the sheets of the group to the tinning pot or other machine in the event one or more of the sheets is accompanied by or contains; an additionalsheet or sheets oris of a thickness;v greater than the predetermined normal thick: ness of a single sheet. In the illustrated embodi- I ment there are shown three sheet calipering mechanisms corresponding to the number of piles of sheets 21, 21a, and 21b. The sheet cali pering mechanisms are so controlled that thesheet calipering operations thereof are performed: simultaneously on all the sheetsof the group, and effect operation of a common control mem, ber in the event one or more; of the ca1 ipered sheets contain an additional or excess sheetior;

sheets or is of an abnormal thickness. The control member may be utilized to interrupt the feed of sheets by the feeder and to stop the conveyor in the usual well-known manner, but, as herein illustrated, it is utilized to operate a common sheet reject or throwout mechanism for diverting all the sheets of the group out of their normal path of travel into a reject sheet supporting tray. In this manner, the abnormal group of sheets is automatically removed from the conveyor, and feeding of successive groups of sheets by the feeder may continue without interruption, resulting in an increased output of fed sheets. The rejected double or plural sheets of normal thickness may then be individualized and placed back on the piles 21, 27a, and 21b together with the rejected single sheets of normal thickness and re -fed.

The sheet calipering mechanisms indicated generally at 63, 64, and 65 (Fig. 2), except for their location in the feeder to act on the separate sheets fed from the piles 2T, Tia, and 21b in side by side relation, are identical in construction, mounting, and operation and a description of one of said mechanisms will therefore sufiice for all of the'same. Before proceeding with the description of the construction, mounting, and operation of one of the sheet calipering mechanisms, it might be mentioned that the center brackets 24 and 52 are so arranged that one bracket 52 is located intermediate the side edges of each pile of sheets 21, 27a, and Zlb, and that one bracket 24 is located above and to one side of each bracket 52. Itmight also be mentioned that the center brackets 52 each contains an anti-friction bearing 66"(Figs. 3 and 6) for supporting and providing frictionless rotation of the feed roller shaft 5|. For purposes of description, each sheet calipering mechanism 63, 64, and 65 will thus consist of the following parts including one bracket 24 and one bracket 52, which brackets, as hereinabove described, also serve to support and provide additional bearings for the cam shaft 23, drop roller shaft 56 and feed roller shaft 5|. Each sheet calipering mechanism 63, 54, and 65 is preferably constructed, mounted, and operated as follows.

Secured in any suitable manner in the hub 61 of center bracket 52 and projecting laterally therefrom in the direction of side frame Ill is a sleeve 68 through which feed roller shaft 5| extends (Fig. 6). Secured by a press fit on the outwardly projecting end of sleeve 68 is the inner race of a ball bearing 69 having its outer race secured by a press fit in the bore of a lower sheet calipering roller it which is substantially of the same diameter as the diameter of the feed rollers 48, and of the feed rollers 41 including the tapes which pass around the latter (Figs. 3, 4, and 6). Calipering roller 10 is formed at one side thereof with a slightly reduced hub portion ll, and disposed within said hub portion is a disc 12 which is engaged over and secured to shaft 5i. Disc 72 is provided in its periphery with a pin ii that projects into a slot 14 formed in the hub portion 1: of calipering roller 1!]. The calipering 'rollers 16 of the sheet calipering mechanism 63,

84, and are thus supported independently of shaft 51 for free and true concentric rotation by sleeves 68 and bearings G8, and are driven continuously from shaft 5| in unison with and at substantially the same surface speed of the feed rollers 48 and tapes 5G by the discs 52 and pins 14. The bore of each sleeve 68 is preferably slightly greater in diameter than the diameter of shaft 8 5| so that any vibration of said shaft and any variation in the concentricity thereof will not be transmitted to calipering roller 10 and affect the sheet calipering operation.

Cooperating with the calipering roller 1i! and disposed above the path of sheet travel is an upper sheet calipering roller 15 (Figs. 3 and 4) which is journalled at 18 on a rearwardly extending arm ll that is loosely mounted adjacent the center bracket 24 on the drop roller shaft 56 for pivotal movement relative thereto. Disposed between bracket Ed and arm Ti and loosely mounted on shaft 56 for pivotal movement relative thereto is a bell crank lever having a rearwardly extending arm l8 and an upwardly extending arm It. Pivotally mounted at on bell crank arm l8 and disposed above calipering roller 75 for cooperation with said roller is a caliper element 8| which is preferably in the form of a segment and provided with two radially spaced laterally projecting pins 82, 82 for purposes to be hereinafter described. Axial displacement of arm I! and bell crank lever i8, i9 is prevented in one direction by the center bracket 24 and in the opposite direction by a collar 83 secured to shaft 56.

Arm I? is yieldingly urged downwardly by a comparatively light compression spring 84 so that the upper calipering roller 15 thereon will engage and press the forwardly moving sheet against the calipering roller W with sufficient pressure to insure positive rotation of said upper calipering roller by the sheet engaged thereby and accurate calipering of said sheet. Spring 84 is mounted on a spring rod 85 having one end pivotally connected at 86 to arm T5 and the opposite end guided in a post 81 secured to bracket 24 and projecting inwardly therefrom to receive said rod. One end of spring 84 engages an abutment on rod 85 and the opposite end bears against post 87. 1

The segment SE of each sheet calipering mechanism 63, 54, and 65 is normally disposed in the full-line position shown in Fig. 3 and such that it is spaced from the cooperating upper calipering roller 15 a distance less than the normal thickness of a single sheet when said roller is engaged with a single sheet of normal thickness, as shown in Fig. 3. This and other desired settings of segment 8i with respect to calipering roller 15 for sheets of different thicknesses that may be handled in the feeder is effected by an adjusting screw 88 (Figs. 3 and l) which is threaded through a suitable opening in a vertical extension 89 of bell crank arm 19 and adapted to engage a hardened steel plug 90 threaded in the adjacent end of bracket 24. R0- tation of screw 88 in opposite directions will result in clockwise and counterclockwise movement (Fig. 3) of bell crank lever l8, 79 about shaft 56 and, hence, lowering and raising movement of segment 8! toward and away from calipering roller '55. Screw 88 is held in adjusted position by a lock nut ea.

Bell crank lever l8, i9 is yieldingly urged in a clockwise direction (Fig. 3) by a comparatively heavy compression spring 92, whereby screw 88 will be firmly pressed against plug 90 to accurately locate segment 8! with respect to calipering roller 75, and segment 81 Will be firmly held in proper position to insure positive rotation thereof by roller 15 when the latter engages an excess sheet or a sheet of abnormal thickness. Spring 92 is mounted on a spring rod 93 having one end pivotally connected at 94 to bell crank arm 18 and the opposite end guided in a post 95 secured to center bracket 24 and projecting inwardly therefrom to receive said rod. One end of sprin 92 engages an abutment on rod 93 and the opposite'end bears against post 95.

' The upper calipering rollers "I and cooperating segments 8! of the sheet calipering mechanisms 63, -64, and 65 are raised and lowered at predetermined intervals, and the operation thereof is so timed that all the rollers I5 and segments SI are raised until the sheets delivered in side by side relation onto the feed rollers 48 and tapes 59 by the sheet forwarding devices have been advanced by the drop rollers 49 a short distance relative to piles 21, 21a, and 21b so that their front or leading edges extend a few inches beyond said drop rollers, at which time the rollers l5 and segments 8| are simultaneously lowered and the upper surfaces of the forwardly movin sheets are simultaneously engaged by said rollers for performance of the calipering operations thereon. For this purpose, the bell crank arm 79 of each sheet calipering mechanism has journalled thereon at 96 a cam roller 9? which is engaged by a cam 98 secured to and rotated by cam shaft 23. Roller 9'! is biased toward cam as by the spring pressed rod 93 connected with the bell crank arm 18. [The 'bell crank levers I8, "I9 of the sheet calipering mechanisms 63, I54, and 65 are thus simultaneously rocked in a counter-clockwise direction (Fig. 3), by separate cams 98 to raise the seg- .ments 8| carried thereby, and are simultaneously rocked in a clockwise direction by the separate sprin pressed rods 93 to lower said segments until the adjusting screws 88 on the respective bell cranks engage the respective plugs 99, at which timeall the segments 8| will be disposed in likedefinite positions for the sheet calipering operations.

Counter-clockwise or segment raising movement of each bell crank .18, I9 is transmitted to the arm 11 associated therewith by a screw 99 which is threaded through a suitable opening in a laterally projecting ear or lug I09 formed integrally with bell crank arm I9 and is adapted to engage a, similar lug .IUI formed integrally with and projecting laterally from arm 'I'I. Clockwise or downward movement of each arm II with the bell crank 18, I9 associated therewith is effected by the spring pressed rod 85 connected with said arm, said rod also acting to yieldingly engage the lug IOI on arm 11 with screw 99 and take up any lost motion between said arm and the bell crank when the latter is rocked to raise segment BI and roller I5 as hereinbefore described. Screw 99 is so adjusted with respect to lug IIII on arm Tl that when segment BI and roller I5 are lowered to sheet caliperin position and the adjusting screw 88 is engaged with plug 99, a slight upward movement will be im-- parted to roller I5 against the tension of spring 84 by a single sheet of normal thickness upon engagement of said roller therewith. In this manner, roller l5 will engage the forwardly moving sheet under spring tension whereby positive rotation thereof by said sheet and accurate calipering of the latter will be assured. It will be understood that this slight upward movement of roller l5 by a single sheet of normal thickness is not sufficient to cause said roller to engage and rock segment 8|, said movement being compensated for in the initial setting of said segment with respect to roller I5. It would also be understood that when effecting initial adjustment of segment BI and any further adjustments thereof with respect to roller 15, the screw as is backed off several turns to permit making of said adjustments, and then returned to its proper adjusted position. Screw 99 is held in adjusted position by a lock nut I92.

Extending transversely of the feeder and past each of the sheet calipering mechanisms 63, 64, and 65 is a shaft I03 which is common'to all said caliperin mechanisms and may, for the sake of description, be termed the main control shaft or member. This shaft I93 is journalled intermediate its ends in suitable bearings in the'center brackets 24, and at its opposite ends in suitable bearings in brackets I94 and I95 which are secured to the side brackets 51 and 59, respectively (Figs. 2, 4, 5, '7 and 8). Shaft I93 has secured thereon a plurality of pendulums I96 (Figs. 3 and 4) which extend rearwardly and downwardly from said shaft and project between the laterally projecting pins 82, 82 on the caliper segments 8|, there being one pendulum associated with each segment. Pendulums I96 normally rest by gravity on one of the pins 82 of the segments 9!, as shown in full lines in Fig. 3. It will thus appear that when the segment 8! of any one of the sheet calipering mechanisms 63, 64, and 65 is rotated in a counter-clockwise direction as Viewed in Fig. 3, to the broken line position, the pendulum IE3 associated with the rotated segment will be raised thereby to the broken line position shown in Fig. 3 and, hence, rock shaft I93 in a counter-clockwise direction as viewed in Fig. 3, or in a clockwise direction 'as viewed in Fig. 7, since said views are right and lefthand views, respectively.

Shaft ifs-E5 may be utilized to control the operation of well-known mechanism for stopping or tripping the feeder and for stopping the conveying means in the event an abnormal condition in the feeding of the sheets from the separate piles 2?, 27a, and 27b is detected by any one of the sheet calipering mechanismsfit, 6 3, and 65, thereby preventing feeding of successive groups of sheets from said piles and presentation of an abnormal group of sheets on the conveying means to the tinning pot or other machine being fed. In the illustrated embodiment, however, shaft I93 is utilized to control the operation of a sheet reject or throwout mechanism for diverting all the sheets of an abnormal forwardly moving normal groups of sheets from piles 2?, 27a, and

.2.'Ib may continue without interruption As shown, particularlyin Figs. 1, 2, '7, and 8, the sheet reject or throw out mechanism and the operating and control means therefor are preferably constructed, mounted, and operated as follows.

Secured to control shaft 93 adjacent its end supporting bracket M25 is an arm IQI (Figs. '7 and 8) which extends upwardly and forwardly from said shaft and have journalled thereon a roller I538. The latter engages the rear longitudinal edge of a vertically extending bar or link I99 which is formed with an abutment I It on its front longitudinal edge and adjacent the upper end thereof. The lower end of bar I99 is pivotally connected at I I I with a forwardly extending arm II2 which is secured to a shaft H3 that ex- 1 1 plates 51 and 58, and has secured thereon a plurality of sheet reject fingers I I4 which extend forwardly from said shaft between the tapes 5E! and normally lie beneath the plane in which the upper reaches of said tapes and the sheets travel. As shown in Fig. 2, the fingers I I6 are spaced along shaft I i3 and across the entire width of the conveyor so that all the sheets moving along said conveyor in side by side relation will be rejected when said fingers are raised as hereinafter described, thus providing a common reject mechanism for the group of sheets.

Reject fingers Ilt are lowered out of the sheet path and to their normal inoperative position, as shown in full lines in Figs. 1 and '7, by gravity assisted by a pull spring I is having one end connected with the free end of arm I I2 and the opposite end connected with a pin H5 secured to and projecting inwardly from the side plate 58 (Figs. 7 and 8). Downward movement of the fingers H4 beyond their normal inoperative position is prevented through engagement of arm II2 with a suitable stop member, such as, a bolt I I! located beneath the free end of said arm and adjustably threaded in a post I 28 which is secured to and projects inwardly from the side plate 58. Bolt Ill is locked in adjusted position by a lock nut I I9.

The upper free end of bar I89 extends through the bifurcated end I26 of a forwardly extending arm I2 I having a hardened steel block I22 secured thereto at said end so as to extend across the front longitudinal edge of said bar (Figs. 1, 2, '7, and 8). Arm IZI is loosely mounted for pivotal movement on a short shaft I23 which is fixed in a pair of brackets I24 disposed on opposite sides of said arm and secured to the tie bar I2. J ournalled at I25 on arm I2I is a roller I25 which engages a cam I27 secured to and rotated by cam shaft 23. Roller I28 is held in engagement with cam I21 by a vertically extending spring pressed rod I28 having one end pivotally connected at I29 to arm IZI and the opposite end guided in an eye-bolt I39 secured to and projecting forwardly from tie bar I3. The spring I3I for rod I23 is mounted thereon between the eye-bolt I30 and a collar I 32 adjustably secured to said rod.

Arm IZI will thus be raised by cam I21 and lowered by spring I3I once during each cycle of operation of the feeder, and the operation of said arm is so timed that it is lowered prior to engagement of the upper caliper rollers 55 with the forwardly moving sheets on the conveyor, and raised when said rollers are engaged with said sheets and performing the calipering operations thereon. The low part of cam I2? is so proportioned that when roller IZEi on arm I2! is engaged therewith during each cycle of operation, the block I22 on said arm will be disposed slightly below the level of the abutment IIS on bar N29 to permit said abutment to extend over said block when bar N19 is swung to the broken line position shown in Fig. '7 in a manner hereinafter described. Bar [I39 is normally disposed in the full line position shown in Fig. 7 so that the abutment Hi? thereon will normally be disposed to the rear of block I22 on arm I2! and out of the path of upward movement of said block, said bar being urged to said position and into engagement with roller I08 on arm IGI by a very light pull spring I33 having one end connected therewith at I5 and the opposite end connected with a pin I35 secured to and projecting inwardly from bracket I95 (Figs. '7 and 8) The operation of the feeder, the sheet calipering mechanisms and the sheet reject or throwout mechanism may be briefly summarized as follows. Assuming that the various mechanisms of the feeder, and the sheet calipering and reject mechanisms have been properly timed with relation to each other, and that the caliper segments BI have been adjusted to provide the proper clearance between the same and the caliper rollers 75 for the free passage of single sheets of a normal predetermined thickness only, the uppermost sheets of piles 27, 21a, and 211) are simultaneously engaged and lifted near the front thereof by the suction cups 34 of the sheet forwarding devices which have been previously swung rearwardly by the described means for this purpose. The sheet forwarding devices are then swung forwardly in unison and carry the lifted sheets in the same direction therewith until the front edges of said sheets extend between the raised drop rollers 49 and the driven feed rollers 48 and tapes 50. The sheet forwarding devices then simultaneously release the three sheets whereupon the drop rollers 49 are lowered into engagement with said sheets and the latter are advanced in side by side relation from the piles 21, 27a, and 21b to the tinning pot or other machine by the cooperating feed rollers 48 and the tapes 50, the sheet forwarding devices in the meantime moving rearwardly in readiness to engage, lift, and forward the next sheets from piles 2?, 2M. and 211).

As the sheets are being advanced in side by side relation from the piles 21, 21a, and 2112 by the sheet forwarding devices, the roller I26 on reject arm I2I is engaged with the low part of cam I2! and consequently said arm will at this time be lowered by spring I3I to its lowermost position, as shown in Fig. 7. When the three sheets have been advanced by the feed rollers 48 and drop rollers 49 so that their front edges extend a few inches beyond the bite of said rollers, the high parts of caliper earns 98 upon continued rotation thereof move out of engagement with rollers 53'! whereupon the caliper bell cranks "58, Is and the caliper arms 'I'I are simultaneously rocked in a clockwise direction (Fig. 3) by springs 92 and 84, thus lowering the rollers I5 and segments 8| carried thereby until said rollers engage engage the stop plugs 90.

the upper surfaces of the forwardly moving sheets and the adjusting screws 88 On said bell cranks The rollers I5, upon engagement thereof with the forwardly moving sheets, will be rotated in a clockwise direction, as viewed in Fig. 3, by said sheets, and will remain in contact with the sheets until they have been advanced by the feed rollers 48 and drop rollers 49 so that their front or leading edges extend partly over the lowered reject fingers I I4. Thereupon the high parts of cams 98 upon continued rotation thereof will again engage the rollers 91 and simultaneously rock the bell cranks l8, l9 and arms 'I'! in a counter-clockwise direction, as viewed in Fig. 3, thus raising the seg ments 8i and the rollers 55 out of engagement with the forwardly moving calipered sheets and holding said segments and rollers in raised positions in readiness for performance of the calipering operations on the next group of sheets fed from the piles 2?, 23a, and 21b during the next cycle of operation of the feeder. While the three sheets are being calipered by the rollers I5, the high part of reject cam I21 upon continued rotation thereof will move into engagement with the roller I26 and raise arm I 2| and the, block I22 carried thereby. The high part of cam I2! is so proportioned that arm I2I will be held in raised position until the caliper rollers 15 have been raised'out of engagement with the forwardly moving sheets and the latter have been advanced by the feed rollers '48 and drop rollers 49 so that their front edges extend beyond the front ends of the lowered reject fingers I I4.

If, during calipering of the three sheets by the rollers I5, there is no additional sheet or sheets adhering to or accompanying any one of said sheets and all three sheets are of the same predetermined normal thickness, the caliper segments 3! will remain stationaryjin the position shown in full lines in Fig. 3. In such event, the control shaft Hi3 will not be actuated, the bar I09 will remain in the full line position shown in Fig. '7, and the block I22 on arm IEI, upon raising of said arm by cam I2l, will merely idle past the abutment I III on said bar. Accordingly, the reject fingers Iii w ll remain in their lowcred inoperative position "shown in Figs. 1 and 7, and the three sheets which are of a uniform predetermined thickness Will then be advanced there- CV61 in side by side relation toward the tinning pot or other machine by the feed rollers 48, drop rollers :9, and tapes 58, and presented to said tinning pot or machine for coating the same or .performing other operations thereon. These operations are performed in the order named on successive goups of sheets as long as all the sheets of each group are of a uniform predetermined thickness, and normal feeding of successive groups of sheets thus proceeds without interruption.

Assuming now that one of the three sheets forwarded simultaneously from the piles 27, 27a, and 2712 by the sheet forwarding devices is accompanied by or contains an excess sheet adhering thereto or is 01" a thickness greater than the normal predetermined thickness of a single sheet. In this event, when the caliper rollers 75 are lowered into engagement with the for- Wardly moving sheets and rotated by said sheets, as hereinbefore described, the roller I5 engaged with and rotated by the double or excess thickness sheet will be raised by said sheet into conassociated therewith to raise said pendulum to the broken line position shown in Fig. 3 and thus rock control shaft I33 and arm I01 in a clock- .,wise direction, as viewed in Fig. 7, whereupon bar IE9 is swung by arm Iii? in the same directionabout its pivot Hi to the broken line position shown in Fig. 7, to dispose the abutment iii on said bar in the path of upward movement of the block 22 on arm I2I. Block I22, upon sub sequent upward movement of arm I by cam I21, will then engage the abutment IIO on bar I09 and raise the latter and the arm II2 whereupon shaft H3 will be rocked in a counter-clockwise direction, as viewed in Figs. 1 and 7, and the fingers II 4 will be raised and projected at an angle across the plane of movement of the upper reaches of the tapes 520, as shown in broken lines in Fig. 1. All the sheets of the abnormal group will then be diverted out of their normal path of travel by the raised and angularly disposed fingers i It and advanced upwardly along said fingers in side by side relation by the feed rollers 48 and drop rollers 49 between opposed delivery rollers I36 and I3? which direct allthe rejected sheets into a reject sheet receiving tray I 38 or other form of receiver, thus preventing presentation of the abnormal group of sheets to the tinning pot or other machine and without havin to stop the conveyor and interrupt the feeding of successive groups of sheets by the feeder. It will be understood that shaft I I3 may also be employed to'effect operation of suitable well-known means for stopping or tripping the feeder and for stopping the conveyor. Hence, shaft H3 may be termed an auxiliary orsecond control shaft or member.

As the rejected sheets are advanced along the reject fingers -I I4 by the feed rollers 48 and drop rollers 49, the ca'liper rollers "I5 are raised outbf o engagement with said sheets as hereinbefore described, whereupon the rotated segment BI is automatically reset by its own weight and the weight of the pendulums I05, at which time the control shaft IE3 is also rocked thereby in a counter-clockwise direction, as viewed in Fig. 7, and the arm I'fil thereon is returned to its normal full-line position shown in said figure. When major portions of the rejected sheets have been advanced by the rollers I36, I31 into the tray I38, the arm I2I is lowered by spring I3I upon continued rotation of cam IZ'I, whereupon bar I59 and reject fingers II4 are lowered by gravity aided by the spring II5 until the arm II2 engages the stop member III, at' which time bar I09 is returned to its normal full-line.

position shown in Fig. 7 by the action of spring I33, and the abutment IIE) on said bar is removed from the ath of upward movement' of block I22, thus restoring said members to their original positions for subsequent operation during the next or succeeding cycles of operation of the feeder.

The delivery roller I36 extends transversely of the feeder above the tapes 50 and is journa'lled at its opposite ends in the side plates 5] and "58 (-Figs. 1 and 2). The delivery rollers 131 which are pressure rollers are a'djustably fixed in spaced relation on a shaft I39 which extends transversely of the feeder and is journalled at its opposite ends in suitable bearings in arms I40 that are pivotally mounted at I4I on the side plates 5'? and 58. The reject tray I38 may'be supported in any suitable manner and by any suitable means (not shown) on the feeder frame or on the frame of the tinning pot *or other machine with which the feeder is associated. The delivery roller I36 is continuously driven from the feed roller shaft BI and at substantially the same surface speed as the feed rollers 48 and tapes 56 by a belt I42, preferably a V-belt,'w'hich passes around suitably grooved pulleys "I43 and I44 that are fixed on the outwardly projecting ends of the feed roller shaft 5| and delivery roller I36, respectively (Figs. 2 and '4).

Thus far the description has related mostly to the construction and operation of the feeder and the sheet calipering and reject mechanisms for feeding a group or plurality of sheets inside by side relation to a tinning pot or other machine during successive cycles of operation of the feeder, and calipering all the sheets of each group during advancing movement thereof, whereby presentation of any one group of sheets to said tinning pot or machine is prevented in the event one or more of the sheets of the advancing group is accompanied by or contains an excess sheet or sheets adhering thereto or is of an abnormal thickness. In feeding a group or plurality of sheets in side by side relation to a tinning pot or other machine acting on said side relation is presented to the tinning pot or other machine, whereby a balanced condition will be maintained in said tinning pot or machine and proper coating of or action on all the sheets of the group will be assured. In the illustrated embodiment, for example, should the feeder during a feeding cycle fail to feed a sheet from either the pile 21 and pile 21b for any reason, the two sheets fed simultaneously from the other piles would be offside and if they are presented in this manner to the tinning pot or other machine, they would cause an unbalanced con dition therein with the result that said sheets would not be properly coated or acted upon and, hence, must be scrapped. However, if the feeder during a feeding cycle fails to feed a sheet from the center pile ZZd for some reason, the absence of the center or intermediate sheet in the group of sheets when presented to the tinning pot or other machine will have no effect on the .proper coating of or action on the remaining sheets of the group since the presence of the outside sheets in the group will maintain a balanced condition in said tinning pot or machine.

Accordingly, novel absent sheet detecting mechanisms are provided and associated with the conveying means and with the outside sheet calipering mechanisms 63 and 65 for detecting the presence and absence of the outside sheets in each group of sheets delivered in side by side .relation to said conveying means, and effecting 1, '7, and 8) except for their location adjacent opposite sides of the feeder to act in the feed roller positions normally occupied by the sheets forwarded from the piles 21 and 21b, are identical in construction, mounting, and operation and a description of one of said mechanisms will therefore suffice for both of the same.

Referring to Figs. 3, 4, and which illustrate the absence sheet detecting mechanism I45, it

will be noted that said mechanism comprises the following parts constructed, mounted, and operated as follows, the corresponding parts of the mechanism I46 at the opposite side of the feeder and illustrated in Figs. 1, '1, and 8 having applied thereto the same reference characters except that they are primed. Secured to cam shaft 23 adjacent the inner side of side bracket I6 and rotated by said shaft is a cam M1 which engages a roller I48 journalled at I49 on a forwardly extending arm I56. The latter is pivotally mounted at I5I on a bracket I52 which is secured to the rear side of side bracket I6. Pivotally connected at I53 with arm I56 is the upper end of a vertical link I54 the lower end of which is pivotally connected at I55 with a rearwardly extending arm I56 that is loosely mountedon the control shaft I03 adjacent the bracket 10,4. Arm I56 is provided with an inwardly profijecting shelf I51 for a purpose to appear hereafter. 7

Arm I56 also has pivotally connected therewith at I the upper end of a vertical connecting rod I58 the lower end of which is pivotally connected at I59 with a rearwardly extending arm i325 that is fixed on a short transversely extending shaft IiiI. This shaft I extends from the side plate 51 to the center bracket 52 of the sheet calipering mechanism 63 and is journalled at its opposite ends in suitable bearings in said side plate and in a bracket I52 that is secured to the front side of said center bracket. Fixed on shaft I6I adjacent center bracket 562 is a rearwardly extending arm I63 which is similar to the aforesaid arm I66 on the opposite end of said shaft. Pivotally connected with the free end of arm I63 is the upper end of a vertical link I64 the lower end of which is pivotally con.- nected at I65 with a sheet detector member or feeler in the form of a bell crank lever having a straight arm I65 and a curved arm 35?. The straight arm I65 extends forwardly beneath the hub 61 of center bracket 52 and between the latter and the lower sheet calipering roller 18 and has the link ISA connected therewith, and the curved arm I61 extends upwardly and forwardly over said hub and between said bracket and calipering roller and has journalled on the free end thereof a roller I68. Detector member or bell crank I66, I61 is pivotally mounted at I69 on a bracket I16 which is secured to the rear side of center bracket 52.

Cam arm I58 is yieldingly urged toward cam I41 by a compression spring I11 to cause the roller I49 on said arm to follow into the lower part of said cam upon continued rotation thereof, said spring being mounted on the connecting rod I553 between a collar I12 adjustably secured to said rod and a bifurcated post I13 secured to and projecting inwardly from the side plate 51. It will thus appear that once during each cycle of operation of the feeder, the detector members or bell cranks $66, I61 and I56, I61 of the mechanisms I45, I46, respectively, through the described connections therefor with the cam arms I56 and I56 will be independently rocked in one direction about their pivots I69 and I59 by the cams I41 and I4? to raise the detector arms I61 and I61 and rollers I68, I68 thereon across the sheet path normally occupied by the outside sheets of the group on the conveyor, and in the opposite direction by the springs I1I, I'II' to lower said arms and rollers out of the sheet path to their normal positions, as shown in full lines in Figs. 1 and 3. The absent sheet detecting operations are so timed that the detector arms I61, I61 and rollers I63, I68 thereon are in their lowered positions while the sheets are being for warded in side by side relation from the piles 21, 21a, and 21b by the sheet forwarding devices and delivered to the feed rollers 48 and tapes 50,

- at which time the caliper rollers 15 are also in their raised positions as hereinbefore described, and are then raised in unison after said sheets have been advanced a short distance relative to said piles by the feed rollers :38 and drop rollers 49, at which time caliper rollers 15 are lowered to engage and caliper the sheets as hereinbefore described.

It is to be noted that when detector arms I61, I61 are raised as aforesaid, the arms I56 and I56 associated therewith are also raised, but no movement will be imparted to the control shaft m3 by arms I56 and I56 since the latter are loosely mounted thereon as hereinbefore de scribed. However, this raising movement of arms I56 and I56 is utilized to rock the control shaft I03 and effect operation of the reject fingers I I4 as hereinbefore described. For this purpose, the arms I56 and I56 have associated therewith other arms I14 and I14 which are secured to the control shaft 153 and provided with adjustable abutment screws I15 and I15 that are adapted to be engaged by the shelves I51 and I51 on the arms I56 and I56. Hence, by reason of the separable connections between the arms I56, I56 and 514, I14 afforded by the shelves I51, I51 and abutment screws I15, I15, the arms I14, I14 and control shaft I63 will not be actuated when the arms I56, 156 are lowered by cams I41, I41 and only actuated when the arms I56, I56 are raised by springs I1I, I1! and the shelves I51, I51 engage the abutment screws I15, I15. It is to be noted that by reason of the loose and fixed arms I56, I56 and I14, I14, respectively, the operation of the control shaft I63 by the sheet calipering mechanisms 63, 64', and 65, as hereinbefore described, is not afiected by the absent sheet detecting mechanisms I45 and I46.

Assuming that both outside sheets are present in the group of sheets delivered in side by side relation onto the feed rollers 48 and tapes 50, and that the leading edges of the sheets are disposed in proper position longitudinally of the conveyor for performance of the sheet detecting and sheet calipering operations thereon. In this event, and with the outside sheets of the group disposed over the lowered detector arms I 61, I61 and rollers I68, I68 thereon, and engaged by the upper caliper rollers 15 and the drop rollers 49, the outside sheets will form an obstruction and, upon. engagement of the rollers I65 and I68 with the undersurfaces thereof, will thus prevent the detector arms I 61, I61 from moving upwardly the full extent. Accordingly, the rollers I49, I49 cannot follow the low parts of cams I41, I41 a distance sufficient to enable arms I51, I51 to rock arms I56, I56 through an are sufficient to engage the arms I14, I14 and rock control shaft Hi3. The reject fingers 1 I4 will then remain in their lowered inoperative position and forward movement of the group of sheets on the conveyor toward the tinning pot or other machine Willproceed as usual provided, of course, that none of the sheets contains an excess sheet or is of an abnormal thickness to cause operation of the control shaft use and reject fingers I I4 by the sheet calipering mechanisms as hereinbefore described. Thereupon the detector arms 51, I61 are lowered to their original positions and the rollers 588, I58 thereon are moved out of engagement with the advancing sheets upon continued rotation of cams I41, Hi1 and engagement of the high parts thereof with the rollers I49, I49, at which time the caliper rollers 15 are also raised to their original positions as hereinbefore described so that said detector arms and rollers and said caliper rollers are in readiness for performance of the detecting and calipering operations during the next cycle of operation of the feeder. It is important to note that when the detector rollers I68, I68 are moved into engagement with the undersurface of the outside sheets as described, the upper surface of said sheets are engaged by the caliper rollers 15 and the drop rollers 49 at transversely spaced points, thus stiffening the sheets and preventing upward movement or bowing of the same by thedetector rollers I68 and I68.

Assuming now that during a feeding cycle, the feeder fails for some reason to feed a sheet from the pile 21 at a time when said sheet should have been fed from said pile alon with the sheets fed from the piles 21a and 211). In this event, and with no sheet present at the feed roller position normally occupied by the sheet fed from pile 21, the upward movement of the detector arm I61 and roller I68 will be obstructed as hereinbefore described by the sheet disposed thereover and fed from the pile 211), but the upward movement of detector arm I61 will not be obstructed and, hence, said arm and. roller 168 thereon may move upwardly the full extent and to substantially the broken line position shown in Fig. 3. Accordinglyfthe roller I48 may then follow into the low part of cam I41 whereupon arm I56 will be raised by spring I1I a distance sufficient to raise arm I56 into engagement with abutment screw I15 and rock arm I14 and control shaft I63. Upon rocking of control shaft I03, the reject fingers I14 will be raised as hereinbefore described and the forwardly moving offside sheets on the conveyor and represented by the sheets fed from piles 21d and 212) will be diverted out of their normal path of travel and directed into the tray 138, thus preventing presentation of said offside sheets to the tinning pot or other machine.

After the reject fingers II4 have been raised, the detector arm I61 is lowered to its original position through engagement of the high part of cam I41 with the roller I49 on arm I56, at which time the control shaft I03 and arms I14, I14 are returned to their original positions by the weight of the caliper pendulums I66 on said shaft which were raised when shaft I03 was rocked under the control of the absent sheet detecting mechanism I45, said raising movement of pendulums I96 at this time merely being an idle movement. After the offside sheets have been directed into the reject tray I38, the reject fingers H4 are again lowered out of the sheet path and to their original positions, as hereinbefore described, and normal feeding of successive groups of sheets from the piles 21, 21a, and 21b proceeds without interruption.

The above-described operations of the absent sheet detecting mechanism I45 are performed in the order described by the absent sheet detectin mechanism I46 in the event the feeder, during a feeding cycle, fails for some reason to feed a sheet from the pile 211; at a time when said sheet should normally be fed from said pile along with the sheets fed from the piles 21 and 21a, therefore, a detailed description of the operation of mechanism I46 is believed to be unnecessary. It is to be noted that the absence sheet detectingmechanisms I45 and I46 will also effect operation of control shaft I63 and reject fingers I14 if, when the sheets are forwarded by the sheet forwarding devices from piles 21, 21a, and 212), one of. the outside sheets fails for some reason to reach the bite of the feed and drop rollers and is not in normal position on the conveying means at the prescribed time.

While the sheet feeder is herein illustrated and described as a three-sheet feeder for feeding three sheets in side by side relation to a tinning pot or other machine from three piles of sheets arranged in like manner, it is to be understood that said feeder may also be employed to feed only tWo sheets in side by side relation, from two piles only, in which case the two piles of sheets are located in the feeder in the positions occupied by the piles 2-1 and 21b and the presentation of the. sheets fed simultaneously from said piles to the tinning pot or other machine is controlled by the sheet calipering mechanisms 63 and 65 and the absent sheet detectin mechanisms I45 and M6. It will also be understood that the feeder may, if desired, be employed to feed sheets successively from a single pile of sheets thereof, in which case the single pile of sheets is located centrally in the feeder, i. e. in the position cupied by the pile 21a, and the presentation of the successively fed sheets to the tinning pot or other machine is controlled by the sheet calipering mechanism 64 only.

There is thus provided in a sheet feeder particularly adapted for feeding a group or plurality of sheets in side by side relation to a tinning pot or other machine, means, as in the sheet calipering mechanism 63, 6t, and 65 and the absent sheet detecting mechanisms I45 and M6 for preventing presentation to said tinning pot or machine of a group of sheets in the event any one of the sheets thereof contains an excess sheet or is of an abnormal thickness or in the event one or the other of the outside sheets thereof is not present therein or is not present in normal position on the conveying means. There is also provided in a sheet feeder adapted for feeding two sheets in side by side relation to a tinning pot or other machine, means, as in the sheet calipering mechanisms 63 and 65 and the absent sheet detecting mechanisms I45 and M6, for preventing presentation to said tinning pot or other machine of the two sheets in the event either one of said sheets is not present in normal position on the conveying means or contains an excess sheet or is of an abnormal thickness, or of one sheet only upon failure of the feeder to feed one or the other of said sheets. The sheet calipering mechanisms and the absent sheet detecting mechanisms are so arranged that the sheet calipering operations and the absent sheet detecting operations are performed simultaneously on the sheets, and that a single control member common to all said mechanisms is controlled thereby. There is also provided an absent sheet detecting mechanism which is simple in construction and reliable in operation for determining whether or not a sheet is present at a time when and at a place where a sheet should normally be present.

Although only a single embodiment of the invention has been illustrated in the accompanying drawings and described in the foregoing specification, it is to be expressly understood that the invention is not limited to said embodiment or to a three-sheet feeder. Various changes may be made, particularly in the design, arrangement, and mode of operation of the parts illustrated, without departing from the spirit and scope of the invention, as will now be apparent to those skilled in the art. For example, the control shaft I 03 or the control shaft H3 may be employed to actuate a clutch, a valve, or any other suitable means for stoppin or tripping the feeder and stopping the conveyor or the forward movement of the sheets thereon when an abnormal condition arises in the feed of the sheets. For a definition of the limits of the invention, reference is had primarily to the appended claims.

What is claimed is:

1. In apparatus of the character described, conveying means for receiving and advancing a plurality of sheets in spaced parallel paths toward a machine, a plurality of detecting devices for detecting the thickness of said sheets, normally inoperative reject means extending transversely of said conveying means and wholly disposed below said paths forwardly of said detecting devices, a common control member actuated by any one of said detecting devices in response to the presence of double sheets in any of said paths, and means responsive to the actuation of said control member for efiecting operation of said reject means and upward movement of the latter to a position angularly across said paths whereby all the sheets will be diverted out of said paths.

2. In a sheet feeder, a conveyor comprising a plurality of transversely spaced tapes for receiving and advancing a plurality of sheets in spaced parallel paths toward a machine, a plurality of sheet calipering devices for calipering said sheets, a plurality of reject fingers pivotally mounted below the upper reaches of the tapes and extending between and along said tapes forwardly of said calipering devices and normally disposed out of said paths, a common control member actuated by any one of said calipering devices in response to a sheet of abnormal thickness in any of said paths, and means responsive to the actuation of said control member for swinging said reject fingers upwardly to a position angularly across said paths whereby all the sheets will be diverted out of said paths.

3. In apparatus of the character described, a continuously driven conveyor including a plurality of transversely spaced tapes for advancing a group of sheets of a predetermined number presented thereto in side by side relation along a predetermined path of travel, detector means for detecting the absence of a sheet from said group, reject means arranged at a predetermined point along said tapes beyond said detector means and movable from a normal inactive position out of the path of travel of the sheets to an active position angularly across said path to cause the sheets of said group to travel in another path diverging from their normal path of travel, and means controlled by said detector means for moving said reject means to said active position when the absence of a sheet from said group is detected by said detector means.

4. Apparatus as defined in claim 3, including sheet calipering means arranged in advance of the reject means for detecting the presence of a sheet of excess thickness in the presented group of sheets, and which also control the reject moving means to move the reject means to active position when a sheet of excess thickness in said group is detected by said calipering means.

5. In apparatus of the character described, a continuously driven conveyor including a plurality of transversely spaced tapes for advancing a group of at least three sheets presented thereto in side by side relation along a predetermined path of travel, detector means for detecting the absence of one of the outside sheets from said group, a plurality of transversely spaced reject fingers pivotally mounted at a predetermined point along said tapes beyond said detector means and movable collectively from a normal inactive position out of the path of travel of the sheets to an active position angularly across said path to cause the sheets of said group to travel in another path diverging from their normal path of travel, and means controlled by said detector means for moving said reject fingers to said active position when the absence of an outside sheet from said group is detected by said detector means.

6. In apparatus of the character described, a continuously driven conveyor including a plurality of transversely spaced tapes for advancing a group of sheets of a predetermined number presented thereto in side by side relation along a predetermined path of travel, a plurality of detector devices for detecting the absence of a sheet from said group, a plurality of transversely spaced reject fingers arranged at a predetermined point along said tapes beyond said detector devices and movable collectively from a normal inactive position out of the path of travel of the sheets to an active position angularly across said path to cause the sheets of said group to travel in another path diverging from their normal path of travel, means normally ineffective for moving said reject fingers to said active position, and a common control element operatively associated with said detector devices for rendering said last-named means eifective to move said reject fingers to said active position when the absence of a sheet from said group is detected by said detector devices.

7. Apparatus as defined in claim 6, including a plurality of sheet calipering devices arranged in advance of the reject fingers for detecting the presence of a sheet of excess thickness in the presented groups of sheets, and which are also operatively associated with the common control element to render the reject finger operating means effective to move the reject fingers to active position when a sheet of excess thickness in said group is detected by said calipering devices.

8. Apparatus as defined in claim 6, wherein the means for moving the reject fingers to active position comprises a cam operated lever and a connecting member which is pivotally connected to the reject fingers and moved into operative engagement with said lever in response to the actuation of the control element by the detector devices.

9. Apparatus as defined in claim 7, wherein the means for moving the reject fingers to active position comprises a cam operated lever and a connecting member which is pivotally connected to the reject fingers and moved into operative engagement with said lever in response to the actuation of the control element by the detector devices and by the sheet calipering devices.

10. In sheet handling apparatus, a conveyor comprising coaxially spaced feed rollers and optween two of said feed rollers and normally disposed inside the periphery of the said two feed rollers substantially in line with the point of contact of said feed and pressure rollers, means mounting said feeler member for upward movement across said sheet path at said point, and operating means for moving said feeler member periodically across said sheet path, said feeler member being held against upward movement by a sheet in normal position on said conveyor and between said feed and pressure rollers, control means, and means responsive to said upward movement of said feeler member across said sheet path in response to the absence of a sheet in normal position on said conveyor for actuating said control means.

11. In apparatus of the character described, a conveyor comprising coaxially spaced feed rollers and opposed coaxially spaced pressure rollers for advancing successive sheets along a predetermined path of travel, absence sheet detecting mechanism operatively associated with said conveyor for detecting the absence of a sheet in normal position thereon, said detecting mechanism comprising a lever arranged between two of said feed rollers with its free end normally disposed inside the periphery of the said two feed rollers and substantially in line with the point of contact of said feed and pressure rollers, a sheet engaging roller journalled on said lever at said end, means mounting said lever for pivotal movement upwardly across said sheet path at said point, and operating means for periodically moving said lever across said sheet path, said lever being held against said upward movement by a sheet in normal position on said conveyor and between said feed and pressure rollers, control means, and means responsive to said upward movement of said lever across said sheet path in response to the absence of a sheet in normal position on said conveyor for actuating said control means.

LEONARD BAKER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 567,266 Ford Sept. 8, 1896 591,094 Dexter Oct. 5, 1897 663,672 Dexter Dec. 11, 1900 1,600,022 Van Heek Sept. 14, 1926 2,129,230: ONeil Sept. 6, 1938 2,145,520 McFarlane Jan. 31, 1939 2,247,466 Baker et al. July 1, 1941 2,294,649 Baker Sept. 1, 1942 2,479,060- Davidson Aug. 16, 1949 

